Area Forecast Discussion

120
FXUS62 KFFC 021959
AFDFFC
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
259 PM EST MON MAR 2 2015
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
SHORT TERM BEGINS WITH WEAK ZONAL FLOW ALOFT GIVING WAY TO WEAK
RIDGING AS AN AREA OF SURFACE HIGH PRESSURE CROSSES THE APPALACHIANS
AND RIDGES DOWN THE EASTERN SEABOARD IN A HYBRID DAMMING EVENT.
MOISTURE CONTINUES TO OVERSPREAD THE AREA BRINGING A CHANCE OF RAIN
TO MAINLY NORTH GEORGIA...BUT HAVE CONTINUED TREND OF AT LEAST
SLIGHT CHANCE POPS ACROSS THE AREA. ZERO SBCAPE TO SPEAK OF TOMORROW
BUT SOME LOW-LEVEL MUCAPE /LESS THAN 100 J/KG/ SHOWS UP IN PORTIONS
OR NORTH GEORGIA ESPECIALLY ON THE NAM...WHICH OF COURSE TENDS TO BE
ON THE HIGH SIDE ANYWAY. SPC DAY2 OUTLOOK DOES NOT HAVE EVEN GENERAL
THUNDER NOSING INTO GEORGIA SO WHILE AN ISOLATED RUMBLE CANNOT BE
TOTALLY RULED OUT...JUST NOT ENOUGH CONFIDENCE TO KEEP THUNDER
CHANCES IN AT THIS TIME.
TEMPERATURES TODAY HAVE RISEN QUITE A BIT HIGHER THAN ANTICIPATED
WITH CLEARING SKIES WHICH MAY VERY WELL HAVE IMPLICATIONS ON LOWS
TONIGHT AS MOISTURE FILLS BACK IN AND CLOUD COVER INCREASES...AND
THUS TRENDED A TAD LOWER WITH OVERNIGHT LOWS. HIGHS TOMORROW NEAR
SEASONAL FOR THE SOUTHWEST HALF OF THE AREA BUT WITH THE DAMMING
BUILDING IN THERE SHOULD NOT BE MUCH OF A DIURNAL CURVE ACROSS
ESPECIALLY NORTHEAST GEORGIA...AND AS IT IS CURRENT FORECAST HIGHS
MAY BE A LITTLE TOO WARM IN THOSE AREAS. FOLLOWING THAT...LOWS
TOMORROW NIGHT WILL HAVE TO BE REEVALUATED DEPENDING ON THE STRENGTH
OF THE DAMMING AND HOW MUCH PRECIPITATION HAS INFLUENCED THE COLD
DOME. HIGH CHANCE TO LIKELY POPS REMAIN ACROSS NORTH GEORGIA THROUGH
THE END OF THE PERIOD THOUGH BY WEDNESDAY MORNING EXPECT VERY LITTLE
IF ANY RAIN ACROSS THE REST OF THE AREA.
TDP
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HAVE LEFT THE LONG TERM ESSENTIALLY AS IS. POTENTIAL WINTER
WEATHER EVENT FOR WEDNESDAY NIGHT THURSDAY MORNING DEPENDS ON
SEVERAL FACTORS...HOW FAR SOUTH THE COLD AIR GETS SEEMS TO BE THE
MAIN UNCERTAINTY. UPPER FLOW REMAINS SOUTHWEST AND IT MAY BE HARD
FOR THE FREEZING TEMPERATURES TO GET TOO FAR SOUTH INTO THE
STATE. THICKNESS PROFILES SHOW A POSSIBILITY OF RAIN...FREEZING
RAIN AND SLEET WITH SOME SNOW INTO THURSDAY MORNING. THIS WILL BE
MONITORED IN UPCOMING MODEL RUNS. REMAINDER OF FORECAST LOOKS OKAY
BUT THERE IS MORE UNCERTAINTY TOWARD THE END OF THE PERIOD WITH
GFS AND ECMWF SHOWING DIFFERING UPPER AIR PATTERNS. HAVE ONLY
TWEAKED THE LAST COUPLE OF PERIODS. PREVIOUS DISCUSSION IS
INCLUDED BELOW.
41
&&
.PREVIOUS...344 AM EST MON MAR 2 2015
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
MEDIUM RANGE MODELS REMAIN CONSISTENT AND IN RELATIVELY GOOD
AGREEMENT THROUGH THE MAJORITY OF THE EXTENDED FORECAST PERIOD.
STILL SHOWING THE WORK WEEK DOMINATED BY SOUTHWESTERLY UPPER FLOW
AHEAD OF THE DEEP WESTERN U.S. TROUGH. THIS KEEPS THE REGION IN A
FAIRLY WARM PATTERN UNTIL THURSDAY BEHIND THE SHARP SURFACE FRONT
THE SWEEPS THROUGH WEDNESDAY/WEDNESDAY NIGHT. STILL SEEING ENOUGH
INSTABILITY FOR CHANCE COVERAGE OF THUNDERSTORMS WEDNESDAY. STRONG
LOW/MID-LEVEL WINDS ALSO STILL HAVE ME A BIT CONCERNED ABOUT AT
LEAST ISOLATED SEVERE THUNDERSTORM POTENTIAL. GOOD LOW-LEVEL FORCING
AHEAD OF THE FRONT BUT UPPER SUPPORT IS LACKING WITH THE MAIN UPPER
TROUGH/SHORT WAVE LAGGING FAR BEHIND THE FRONT. GFS AND ECMWF ALSO
STILL INSIST ON BRINGING IN MUCH COLDER AIR AS EARLY AS LATE
WEDNESDAY NIGHT WITH RESIDUAL MOISTURE AND THE INFLUENCE OF THE
UPPER SYSTEM SQUEEZING OUT SOME LOW QPF PRECIPITATION. UPPER FLOW
REMAINS SOUTHWESTERLY THROUGH THURSDAY AND LOWEST THICKNESSES REMAIN
WELL NORTH OF THE STATE. WILL NEED TO WATCH TRENDS FOR THE
POSSIBILITY OF SOME WINTRY MIX ACROSS THE NORTH. GFS AND ECMWF BOTH
SHOW A GOOD TEMPERATURE RECOVERY INTO THE WEEKEND AFTER A THE SHOT
OF COOL AIR THURSDAY THROUGH FRIDAY MORNING AS THE UPPER FLOW
REMAINS GENERALLY ZONAL OVER THE SOUTHEASTERN U.S. AND THE HEART OF
THE COLDEST AIR REMAINS WELL NORTH OF THE STATE. MAINLY DRY AS
WELL...HOWEVER BOTH MODELS SHOW SOME PRECIPITATION POSSIBLY SURGING
NORTH INTO CENTRAL GEORGIA SATURDAY AS SURFACE LOW PRESSURE SPINS UP
OFF THE GEORGIA/CAROLINA COAST. NOT REAL CONFIDENT WE WILL SEE
ANYTHING SIGNIFICANT WITH THIS BUT SLIGHT CHANCE OR LOW CHANCE POPS
MAY BE APPROPRIATE.
20
AVIATION...
18Z UPDATE...
VFR CIGS ENCROACHING FROM THE EAST FOR AHN/MCN AND METRO TAFS.
SHOULD SEE CONTINUED VFR FOR A WHILE AHN BUT MCN/METRO TAFS MAY BE
IN AND OUT FOR A WHILE. EXPECT ALL TO DROP TO MVFR LATER THIS
EVENING AND IFR AROUND 06Z OR SHORTLY THEREAFTER. COULD SEE LIFR
CONDITIONS BY SUNRISE ESPECIALLY FOR THE METRO TAFS WITH -RA.
WINDS NW 5-10KT INITIALLY SHIFTING TO NE WITH THE LOWER CIGS AT
06Z. WINDS SHOULD CONTINUE TO SWING AROUND TO E OR SE BY TUESDAY
MIDDAY.
//ATL CONFIDENCE...18Z UPDATE...
MEDIUM ON ALL ELEMENTS.
TDP
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 46 49 48 71 / 90 90 40 50
ATLANTA 50 58 54 69 / 90 90 30 50
BLAIRSVILLE 45 51 48 61 / 90 90 80 70
CARTERSVILLE 47 56 53 67 / 90 90 50 60
COLUMBUS 55 72 58 74 / 40 40 20 40
GAINESVILLE 44 49 46 66 / 90 90 60 50
MACON 54 67 56 76 / 60 50 20 30
ROME 46 58 54 64 / 90 90 50 70
PEACHTREE CITY 50 63 55 71 / 80 70 30 50
VIDALIA 55 67 59 81 / 40 30 10 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TDP
LONG TERM....41
AVIATION...TDP